I. Field of the Invention
The present invention relates to contrast dispensing systems.
II. Description of Prior Art
Contrast dispensing systems are well known and provide a mechanism for selectively coupling a source of contrast media, such as from a pressurized bag or bottle, to a patient through a manifold and syringe structure. Contrast dispensing systems typically have a spike at one end designed to selectively engage the contrast media source and an outlet luer connector at the other end adapted to attach to one port of the manifold. Another port of the manifold is connected to a syringe. The syringe and manifold may be manipulated to pull contrast media into the syringe, and then to expel same back out to the patient through yet another port of the manifold.
The media is usually supplied in bulk volume far in excess of that needed for one patient""s purposes. To reduce waste, many contrast dispensing systems include a reservoir between the spike and the luer connector to temporarily hold a quantity of the contrast media. A quantity of the contrast media may be loaded into tile reservoir from the source. The media is then taken from tile reservoir by manipulation of the manifold and syringe to dispense the contrast media to the patient. Thereafter, part or all of the contrast dispensing system may be disposed of and a new system put in place for the next patient so as not to waste the remaining contrast media in the bag or bottle. In an effort to avoid cross-contamination between patients, many such systems include a reusable set carrying the spike, a disposable set carrying the outlet luer connector, a pair of mating luer connectors for selectively joining the reusable and disposable sets, and a check valve downstream of the spike. One large container of contrast media may then be used with multiple patients by switching out the disposable set between patient uses.
Typical contrast dispensing systems include a number of different components such as tubing, valves and luer connectors and the like which represent significant cost both in materials and in terms of labor to assemble the components into the respective reusable and disposable sets. Further, the reservoir has a relatively large diameter compared to the tubing and other components of the system and thus presents the concern that as contrast media enters the reservoir, the entering fluid will free fall onto the top surface of the media in the reservoir creating bubbles. One approach to avoid the formation of such bubbles is to locate a deflector plate below the inlet port of the reservoir so that the fluid will fall into the plate and then be dispersed so as to sheet-off around the periphery of the reservoir adjacent the wall thereof. One drawback to the use of a deflector plate, however, is that the incoming fluid has a tendency to free fall against the plate and splatter. The splatter might be a source of bubbles. Also, where the reservoir is vented, as is typical, the splattering contrast media may interfere with the operation of the vent thus necessitating complex venting structure. Another alternative is to include a downwardly directed, and angled or bent, tube which communicates from the inlet port down into the reservoir and against the wall thereof. Such a bent tube confines the media to avoid splatter, but may have drawbacks of its own. The lube itself may become immersed in the contrast media. Also, all of the incoming contrast media is forced into one location against the reservoir wall.
The present invention provides an improved contrast dispensing system which overcomes the abovementioned drawbacks. To this end, and in accordance with the principles of the present invention, the reservoir is in the disposable set with the check valve directly attached to the inlet port of the reservoir, and the disposable set mating luer connector attached directly to the check valve. As a consequence, the cost of the tubing that would normally have been therebetween, as well as the additional cost of mounting the components to respective ends of the tubing, is eliminated thereby reducing cost.
In accordance with another aspect of the present invention, the reservoir has a chamber the top of which is integrally molded plastic having an inlet port at the top thereof, and a lateral pipe extending across the underside thereof. The lateral pipe is adjacent to, and advantageously has its upper extent defined by, the underside of the chamber top so as to be held at the top of the chamber away from the bulk of contrast media therein. The lateral pipe has an upper tap communicating with the fluid inlet port and a pair of lower cut-outs at opposite ends of the lateral pipe. The fluid coming into the chamber first passes through the inlet port and directly through the tap so as to be confined within the lateral pipe. The confined media is thereafter dispersed at opposite ends of the pipe into two different locations through the cut-outs. As a consequence, the drawbacks of both the deflector plate and the bent lube are avoided.
The chamber top may further have an integrally formed vent port for venting the chamber. Advantageously, the vent port is out of alignment with the lateral pipe. In accordance with a yet further aspect of the present invention, a flip cap, such as is found on vented spikes, is provided by which to selectively close the vent port. The nip cap may be in the form of a nip cap assembly with a spout and hinged cap, or may be a hinged cap attached directly to the vent port. The flip cap avoids the use of costly or complex venting structures to thereby further minimize cost, for example.
Advantageously, the chamber top is a separate component from the chamber. In this regard, the chamber has an enlarged upper opening and an integrally molded plastic cap member is provided to close that upper opening, with the cap member having the inlet port, lateral pipe and, if provided, the vent port.
By virtue of the foregoing, there is thus provided an improved contrast dispensing system which overcomes certain drawbacks of prior contrast dispensing systems. These and other objects and advantages of the present invention shall be made apparent from the accompanying drawings and the description thereof.